WHEN one examines the development of thought from the time of the early Greeks to the present, one finds that science and philosophy have in general ever kept pace in development and that their relation to each other has always been one of mutual and reciprocal suggestiveness. At certain times, of course, it has been the one, at other times, the other that has been dominant in its influence; but at the beginning, granting this to have occurred among the Greeks, neither was first, for both arose and for a considerable period developed together as an organic whole. The subsequent differentiation of problem and of method, although it can not be denied to have had its incipience in ancient thought, was in almost total abeyance up to the time of the Renascence, and is, of course, one of the distinguishing characteristics of modern thought. As a result of, or as identical with, this differentiation, we have to-day not only the great diversity of special sciences, but, as included in these, we have also bodies of systematic knowledge or "doctrines" which to many seem far removed from the practical and the factual. As good examples of such there may be cited the Hegelian philosophy, non-Euclidean geometry, the theory of assemblages, etc. However, not only do such bodies of knowledge or "doctrines" seem to be far removed from an empirical basis, but, more than this, they are often cited as standing in thorough-going opposition to the empirical sciences, and accordingly are frequently treated as pure speculations. To what extent this stigma is a merited one, I will not here discuss, but I shall be content to assert merely that an examination of their development shows clearly that these "doctrines," or whatever they may be called, have grown out of an earlier period of thought in which their progenitors were "near relatives" to the members of the distinctly empirical group. Accordingly, the influence of empiricism is not really lacking in them, but, rather, they are the products of the process of making explicit that which is at least held to be implied or involved in certain systems, philosophical and scientific, which are in direct contact with empirical problems and methods. Thus, as illustrating this and as forming a well-known and generally accepted instance of philosophical development, it may be said that Hegel goes back to Kant, Kant to Hume (in part), Hume to Berkeley, and Berkeley to Locke; and Locke worked out his philosophy, which concerned primarily the question of the "origin, extent and validity of knowledge," in thorough-going dependence on the mechanistic views and science of his time.

Although philosophy may at times, then, seem to get far away from contact with the empirical and the practical, still this may well be only a "seeming," and there may be and generally is a very genuine continuity of influence and of knowledge through the threads of that consistent and rigorous reasoning which forms the discovery of implications and presuppositions. But even a remoteness of this kind is not always the case. Far more frequently, indeed, has there been intimate contact and close relationship, if not within the mind of one man, then as within that larger whole which we call the Zeitgeist, whatever interpretation may be given to this.

As concerns scientists and philosophers, it must be admitted that all of them are educated and develop with that whole body of knowledge which the human race has won theoretically accessible to them. But specialized environment and congenital predisposition really limit this accessibility considerably, and together result in specialized interests and specific development. But this means only that from a great body of knowledge certain parts are selected and become revivified in the mind of some individual, to furnish the basis for further development, for originality, for discovery, for advance. Yet as this process occurs, it issues in a two-fold result. There is a certain unity in knowledge, not of that kind which means that any part is theoretically or a priori deducible from any other part, but in the sense that there are many parts or aspects of reality to be known, and that knowledge of them must form a logically consistent whole. Now education and training may result in a mind which is aware of all this, in a mind, therefore, which, although it is fully informed, and critical, and constructive in some special field, is also fully aware that this field is but a part of a larger whole and that through this relation special investigation gets its significance and importance. Such a mind may be said to be philosophic, or, if one prefers, scientific in the best sense of the term. On the other hand, intellectual development may result in a mind which is seemingly unaware, even ignorant of the history of the race, of its thought, of its hopes and aspirations, a mind which accordingly finds the summum bonum only in one line of thought and investigation, which ignores or even denies the relation of this to a larger whole, because it is ignorant of this whole, and which accordingly pursues its own way along the straight and narrow path of only highly specialized investigation. While one must not speak disparagingly of such minds, since the history of thought shows quite clearly that to these also are due very important contributions to knowledge, still of such a mind it must be admitted that it has the defects of its qualities, namely, that it is in danger of wasting its strength on that which is not significant, and that in studying, for example, the problem of life it frequently forgets both what life itself is as well as how to live.

It is very distinctly to the former type of mind that Professor Brooks belonged; for, keen-sighted pioneer and influential biologist that he was, he was also in thorough sympathy with life and the living in all of their aspects, past, present and future, emotional, intellectual and religious. Perhaps for that reason, too, he was the great teacher and the inspirer of men that with one acclaim he is acknowledged to have been. Technical philosopher he was not, sophisticated philosopher he was not, but sympathetic philosopher he was, and in this respect) since he was biologist also, he was unusual. Contributions to philosophy, also, he did not make, but rather, conversely, he let philosophy make contributions to him, and in. this he was again unusual. And yet all the time he was on the lookout in the various fields and aspects of biological science for that which was of genuine significance, for that which had a bearing on some of those great questions whose solution is of paramount interest and importance and which, therefore, are eternal questions.

These statements concerning Professor Brooks will be made more convincing by considering some of the typical instances in which he brings philosophy and science together. In fact, it is only such instances that can be cited; for of system, either in philosophy or biology, Professor Brooks was quite innocent. Significant and typical of the general attitude which he took, and forming indeed a discussion of one of the most salient problems in biology, physics and philosophy, are the data, the arguments, etc., advanced in Lecture II., entitled "Huxley and the Problem of the Naturalist," in The Foundations of Zoology. Here Professor Brooks cites in particular Huxley*s statement: "If the properties of water may be properly said to result from the nature and disposition of its component molecules, I can find no intelligible ground for refusing to say that the properties of protoplasm result from the nature and disposition of its molecules," and follows this with comments which amount to his taking this position: Huxley's statement can be granted to be valid, but, so granting it, it does not mean that there is or ever can be the possibility of an a priori deduction of the properties of protoplasm from those of its constituents, but that the connection between these must be bridged by induction. For the properties of protoplasm, or indeed those of the organism at any level are not the additive result of those of the parts, but contain something quite new. Thus Professor Brooks indicates the limitations of the mechanistic view of life, limitations which, however, are found as well in the inorganic realm, and which, therefore, demand that in applying theoretical mechanics to nature, either inorganic or organic, an appeal must always be made to experimentally obtained fact in order to discover those constants which are actually found and used in the equations of applied mechanics (vide the gravitational constant). It is the failure to make this distinction between theoretical and applied mechanics, with a resulting misinterpretation on both sides, that has conditioned psychologically the tenets of those two schools, namely, the vitalistic and the mechanistic, between which there has been so much discussion of recent years. In his attitude toward mechanism the adherent of each school has in mind a different thing, with the consequence that there is no genuine joining of issue so far as the fundamental problem is concerned, while there may be and, I think, really is a genuine agreement in regard to it. Thus, in opposing the view that the organism is a mechanism, the vitalist tacitly means that it is not a mechanism in the sense of pure, theoretical mechanics, i. e., of the "geometry of motion," as a deductive system; and in this he is right. But he really also always admits, at least tacitly, that the organism is a mechanism in the second sense, i. e., that, although it has properties which can not be deduced from those of its parts, the former nevertheless result from or are determined by the latter.[1] On the other hand, the mechanist, in opposing vitalism, first fails to make clear that his own position is that the organism is a mechanism in the second sense, and, secondly, wrongly considers the vitalist to be opposing this second view, whereas he is really opposing only the first, the purely theoretical, deductive, mechanistic position.

This solution of the problem is, in fact, recognized by Professor Brooks, and the development of its consequences forms the chief part of his philosophical position, as will be seen subsequently, but it is a solution which, as demanding that the actual properties of nature at any level of synthesis must be found by observation and experiment, both allows that the organic realm has certain properties which the inorganic world has not, and yet that these should be interpreted and treated mechanistically in the second sense. Most intimately connected with this whole question are a number of other philosophical considerations to which Professor Brooks gives much attention. It is from these that he arrives at that which is really his ultimate philosophical position, although, it must be admitted, this is not a very complex or sophisticated one. For Professor Brooks, although he cites and quotes from such sophisticated thinkers as, e. g., Plato, Berkeley and Kant,, is predominantly (he is not always consistent) a realist, first "naïve," and then "critical." Thus, although he dedicates his "Foundations" to Berkeley, and quotes him oftener than any other philosopher, he never seems quite to grasp this philosopher's subjective idealism. And as with Berkeley, so with the others; for example, he never quite gets hold of Kant's phenomenalism. It is Hume, however, who, through that analysis of causation which made him famous and which constitutes the basis for the logic of induction, is of dominant influence on Professor Brooks. The results which Hume obtained are, as is generally well known: (1) that, tracing our concept of cause back to its origin in perception, there is given here only sequential and factual but never necessary connection; (2) that, however, from the experience of frequently repeated specific sequences, a belief in their regular and uniform and even necessary occurrence is generated, or, more generally, that a belief in a universal, necessary order is formed. (3) The belief is justified and is of value practically, but nevertheless, that there is a universal and necessary regularity or order is a pure assumption, or (Mill) it is itself that generalization, by induction from a limited number of cases, which lies at the basis of all specific inductions and gives the "inductive syllogism." All this means that, although a purely deductive theoretical mechanics as ={\displaystyle {{\ce {=}}}} "the geometry of motion" is possible and as such may be identified with determinism, this can be applied to nature only by finding the numerical values for certain functions or properties or qualities experimentally and factually. It means, accordingly, that in just this respect nature is not deductive, is not determined, and that the view that it is "order" is an assumption neither proved nor provable. This does not mean that the same cause under the same conditions does not bring about the same effect; it may, or it may not, but that this is the case is simply the same assumption over again.

It is on the basis of this criticism and analysis of causation, of "order," etc., that Professor Brooks discusses very interestingly such topics as the "Philosophy of Evolution," "Paley and the Argument from Contrivance," "The Mechanism of Nature," etc. If mechanism is to be equated with determinism and "order"—and that is all that it really means to the majority of biologists as well as to the majority of people—then it also is, like them, as above explained, only a pure assumption. But the possibilities or consequences resulting from this are interesting and important. For, with it unproved that there is that kind of continuity and causation and "order" and determinism which would make a purely deductive knowledge possible, there is the logically valid opportunity for spontaneity and genuine discontinuous origin and freedom and teleology and purpose; and yet all of these are quite consistent with that other view of "order," etc., which means that, when specific instances of these have once been discovered by induction, the presumption and the probability is that under the same conditions they will recur. But this simply means that there is a genuine evolution and advance which is at once compatible with mechanism in the above second sense of the term and which yet, as made up of the appearance of new existents, is itself irreducible to continuity, and is uneliminable.

But it is in substance just this view which Professor Brooks accepts and defends in one way or another in a number of Lectures of the Foundations. In order to carry confirmation to the reader's mind that this is the case a few typical passages may be quoted. Thus we find Professor Brooks saying; "So far as I can see, the reduction of all nature to mechanical principles would mean nothing more than that all phenomena of nature are orderly."[2] "When we say nature is orderly, we mean each event may be a sign which leads us to expect other events with confidence."[3] "When, as commonly happens, we change will into must, we introduce an idea of necessity which most assuredly does not lie in the observed facts."[4] Of peculiar interest, since, in perfect agreement with Professor Brooks's general view as above expounded, it reveals his position as to the relation of mind and matter, is the statement that "if such a discovery (i. e., that these two worlds are different aspects of one and the same world reduced to mechanical principles) should ever be made. . . I can not see how it could possibly show that mind is anything but mind."[5] Briefly, this means that if consciousness were found to be, for example, energy, it would be that kind of energy which would have just those properties which consciousness is found empirically to have. Professor Brooks would then bring mind itself within nature, i. e., he would treat it, like other things, quite empirically, and this, I think, is the correct position. But it is a position which has interesting consequences! For, on the one hand, let his interpretation of causation and "order," etc., be remembered. Now Professor Brooks holds that this same interpretation applies also to mental events; the "order," causation, etc., here are factual only to the limited extent actually observed; beyond that they are assumptions. But what is it that makes the assumptions? Why the mind itself, which either is, by the same interpretation, simply the series of mental events, or, if not this, is something more. In the former case we have, then, that which is assumed "order," namely, mind, assuming "order" elsewhere, and so on again and again. Consistency demands, then, that it be admitted that that which may be indeterminate, namely, nature, is known by that which is also indeterminate, namely, mind! But the consistency is itself an element in this latter indeterminateness. The situation thus resulting is, of course, a perplexing one; for, to look at it from a slightly different angle, it means that Professor Brooks as evolutionist makes mind and life, with their assumed "order," etc., develop in response to the "order" of nature;[6] but this response is itself only another term for causation, and must, in order to ensure consistency, itself be interpreted like other cases of causation. But this means that everything is brought within a causal "order" which is held to be only assumed but not proved or provable. And yet it would seem that the very attempt to ground this general view presupposes the contradictory position, namely, that there is a causation, a necessary connection, a unique determination and "order," which are more than assumed. That there is this causation is, however, a view quite compatible with the discontinuity view previously advanced.

Professor Brooks is seemingly not aware of this last possible supplementation of his view, but yet he says nothing which would contradict it. By it the causal connection, discontinuous though it be at certain points, the "order," etc., are more than assumed; although assumptions may be made about them, they are factual.

In accordance, now, with this whole general position, Professor Brooks (rightly) finds freedom quite possible logically because, as a fact, it is quite compatible with "order," and does not mean disorder, nor yet ultimate necessity. "We know we are free to do as we like; and we also know there are reasons why we like to do as we do." Briefly "The reduction of all the phenomena of life to mechanical principles would show that our likings and dislikings are what they might have been expected to be," and "would not disprove the reality or the value of any one thing we discover in our nature."[7]

Quite in line with all this is also the "immanent teleology" which Professor Brooks accepts and which may be made clear by a quotation both apt and amusing: "He who admits that cats are part of nature, and that skill in catching mice is important to the race of cats, must admit that nature is, so far, useful to itself."[8] Thus the teleology falls within the "order" of nature, is quite compatible with it, and indeed applies to a special group of phenomena within this (assumed) causal order. Either description may be made and both are correct.

Concerning the other philosophical aspects of Professor Brooks's writings much need not and indeed can not be said. To be sure, all through the Foundations he is continually quoting from some philosopher, or is raising some philosophical problem, but further than this he does not go. He does not contribute very much at least to the solution of these problems, but, rather, chooses certain statements and points of view of the philosophers as contributing to his own views. But he thus at all times reveals the heartiest sympathy for the results of the philosopher's reflections. "Whether it is desirable to place a prohibitory duty upon philosophical speculations or not, it is utterly impossible to prevent the importation of them into the mind," he says, and further raises the question if it is "not a little curious to observe that those who most loudly profess to abstain from such commodities are, all the while, unconscious consumers, on a great scale, of one or another of their disguises or adulterations?"[9] In this spirit he recognizes that such philosophical problems as those of "knowledge" and "consciousness," of the "principles of science" in general, of cosmology, and, more specifically, of psychology and ethics, are problems which must be solved in order to make the scheme of knowledge complete. What he does not recognize clearly, or at least does not develop, is the fact that, whereas the greater part of biology is consistent with any one of a number of philosophical systems, it is through evolution that a particularly strong leverage is secured by which it can be shown, perhaps, that only one point of view, namely, evolutionary realism, is the correct position; but just how this is the case I can not here demonstrate.

Some of the specific problems above mentioned are indeed discussed by Professor Brooks in some detail, but not very satisfactorily. A few lectures are almost purely biological, with only now and then a philosophical reference, but in general it may be said that, even including these. Professor Brooks is philosophizing all through the Foundations as well as in his other writings, and that in this characteristic rests his unusualness as a biologist. For while, of course, it must be admitted as a well-known fact that his philosophical interest did not lead him to give up the exact observational investigation of detailed problems, one must go further, I think, and say that it was this same interest also that actuated and stimulated him in all such investigations by placing him ever on the lookout for the significant and important task. But yet at the same time he did not ally himself with any specific and definite constructive metaphysical system, not even with that of Berkeley. In fact, it may be said that with the real inner meaning of the majority of the great historical systems Professor Brooks seems to have been unacquainted. It is, rather, by Virtue of his openness of mind, of his search for significant problems, and of his motivation by the spirit of philosophical investigation and criticism, that he not only allies himself with philosophy, but was himself a philosopher, and in all this he furnishes an example most worthy of imitation, if not of emulation, by the investigator in any special field of scientific research.

↑Cf. Driesch in various places in such volumes as "Naturbegriffe und Natururteile" and "The Science and Philosophy of the Organism."